Many existing computer systems include audio playback functionality. Computer systems may incorporate audio playback functionality into the processing system or subsystems. An audio codec (coder/decoder) may be used to convert digital audio data into an analog audio signal for playback by an audio device, such as speakers coupled to a computer. An audio controller may provide an interface between the audio codec and the processing components of the computer. In some computer systems, an audio controller may be included in the chipset of the processing system. The audio controller may send and receive audio data streams to and from the audio codec over an audio data link.
In some computer systems, particularly mobile computer systems, power management has become important. Power management may be accomplished by completely, or partially, shutting down computer components, such as the central processing unit (CPU), chipset, hard disk drive, display, and other input/output (I/O) devices, when the computer is not performing operations. A processing system, for example, may have a number of different power states, also known as sleep states. The processing system may operate in a high power state when it is actively being used and in a low power state during periods of relative inactivity. During low power states, the processing system (e.g., the CPU and/or chipset) may cease communications with and control of other resources. When an audio controller (e.g., within a chipset) is communicating with an audio codec, therefore, the processing system including the audio controller may be prevented from operating in a low power state.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.